A heat pump is designed to extract renewable heating energy from the environment – from the air, groundwater and the ground, and transfer this energy to the heating circuit.

The conditions of the building and plot determine which heat pump system is best suited. Generally, groundwater, the ground itself or ambient air can serve as heat suppliers, each of which is "tapped" in different ways. The heat source chosen for generating thermal energy determines the type of heat pump used.

Air as heat source

Air is available everywhere in unlimited supply and OCHSNER has developed horizontal split system technology even further, to make air source heat pumps more economical than ever. This system is great for new build and even better for modernising heating systems in existing buildings,

where disturbing the ground is generally undesirable and costly. Technical innovations by OCHSNER enable the efficient use of air as the heat source, even at low outside temperatures. Our heat pumps are characterised by their high operational reliability and low noise emissions. Air source heat pumps are also well suited for use in dual mode systems.

Active cooling: in active cooling mode, the heat to be dissipated is transferred by means of an outdoor evaporator, which technically becomes a condenser. Active cooling is possible with all models of the GMLW, AIR BASIC and AIR STATION series.

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Ground as heat source – direct heating

The ground is a free and generous heat store providing an ideal heat source. Horizontal collectors work day and night, continuously harvesting what is, in essence, stored solar energy.

When sized correctly, sufficient source energy will be available even in deepest winter. Direct ground heat systems (also referred to as direct evaporation), will enable you to achieve the lowest possible operating costs of all currently known geothermal collector systems. You will utilise about 4/5th free energy from the environment. The heat transfer medium in the heat pump circuit is free of chlorine and is ozone-neutral. It picks up geothermal energy directly via the seamless duplex pipes of the horizontal collector (copper, PE protective sleeve). This is achieved by the direct evaporation of the refrigerant inside the horizontal collector.

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Groundwater as heat source

Where groundwater is available at an acceptable depth and in sufficient amounts, it offers the best possible seasonal performance factors. A constant temperature of 8 to 12 °C guarantees an optimum heating operation. This requires two wells to be constructed – one delivery and one return well. The return well should be at least 15 metres away from the delivery well in the flow direction of the groundwater. 1 kW heating output requires approximately 250 litres per hour groundwater. The capacity must be verified by a continuous pump test. The amount of suspended matter in the water must not exceed or undershoot certain thresholds, so a water analysis must be carried out. A permit from the local water board is required.

Active or passive cooling: the use of water as a heat sink is suitable for both active and passive cooling of building interiors.

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Ground as heat source – brine

With this system, geothermal energy is picked up by means of a brine circuit and transferred to the heat pump. Geothermal brine collectors can be installed in three different ways: where there is sufficient land available, horizontal collectors are the most affordable option. The area covered depends on the method of construction and thermal insulation level of the building, as well as ground conditions. A spiral-shaped trench collector would be an alternative that takes up less physical space. Geothermal probes which require deep boreholes, can also be set into the ground. These are typically set to a depth of 100 metres each, and are ideal when little space is available. In many locations, these require a permit from the local water board. Active or passive cooling: in active cooling mode, heat is "pumped" from the building interior in summer, using the existing heating system, and transferred to the ground. In active cooling mode, the maximum cooling capacity will still be available, even after several weeks of hot weather. 

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Highest efficiency

For almost 40 years, OCHSNER has been concentrating exclusively on the development and manufacture of highly efficient high end heat pumps. Every OCHSNER heating heat pump is manufactured specifically to your requirements using only high grade components. As part of commissioning, your system is adapted to suit your individual circumstances and conditions. To safeguard your investment in the long term, we recommend your heat pump is serviced regularly. This assures you of permanently low running costs, it extends the service life of your system and prevents possible faults.


On the safe side

In many respects you'll be on the safe side with OCHSNER. Heat pumps use free environmental energy – a heat source that never fails. 

Furthermore, OCHSNER heat pumps are built to a high quality standard and are designed for a long service life. Not only is close attention paid during quality control at the factory, the correct installation of the entire system, which is carried out by our system partners, is also of critical value to us. Consequently, our quality control procedures also include the documentation of all system data. This data also forms the basis for OCHSNER's efficient customer service. 

Benefit from our expertise and experience gained through decades of research, development and production at our site in Austria, and proven in over 130,000 installed systems.



OCHSNER heat pumps are true all rounders. They provide the standard functions of heating, cooling and DHW heating. However, with OCHSNER, you can also heat your swimming pool, integrate a PV system and more besides.

OCHSNER heat pumps operate automatically and require little servicing. You will not have to contend with oil tanks, buying pellets, paying a chimney sweep, or worry about servicing a burner or organising a flue gas test. Ash disposal and the servicing of complex mechanical appliances are not an issue for you.

Just enjoy the convenience of it all. OCHSNER focused on user friendliness in the design of its OTE home climate manager heat pump control system. Advanced technology offers you the greatest convenience, maximum energy efficiency and the highest degree of operational reliability.

Environmentally responsible

For you and your environment

OCHSNER heat pumps utilise solar energy stored in the air, in water or in the ground, thereby making a valuable contribution to climate protection. They operate with non-toxic, ozone-neutral and non-flammable safety heat transfer media.

Those who opt in favour of a heat pump not only reduce CO2they also avoid annoying fluctuations in oil and gas prices and the fear of fuel shortages.

In addition, dependence on uncertain supplies from abroad is no longer a risk factor to be considered. You won't need to worry about where your fuel is coming from in 20 years' time or thereafter.

For new build and heating system modernisation

Heat pumps are suitable for new build as well as modernisation projects. Regardless of whether your building has underfloor heating, wall-embedded heating or radiators – OCHSNER was the first manufacturer, many years ago, to launch a range of heat pumps with flow temperatures of up to 65 °C, now extended to 68 °C through the latest developments. Operation of existing heating systems with conventional radiators is now possible.


The efficiency values of an OCHSNER heat pump will help you to reduce the total outlay of building and system technology right now. Using OCHSNER high efficiency heat pumps, you will have no problem meeting applicable standards and building regulations (EnEV, KfW Haus [German reconstruction credit institute], energy performance certificate, etc.). And this with no investment in thermal insulation or system technology. Savings achieved in the reference building according to DIN 18599 amount to several thousand euros, for example. The significantly better performance data achieved by OCHSNER, compared to standard values, also provide a basis for improving energy performance certificate values (CO2 reduction and primary energy demand).


Today, an OCHSNER heat pump system represents the best and safest investment, particularly in uncertain economic times. Savings of up to 50 % or more on heating bills bring a higher rate of return than any savings account. Increase the value of your house as well, by installing a heat pump, and enjoy higher interest rates in the form of savings on running costs. An energy saving heat pump heating system raises the value of your property significantly, should you ever want to sell.

A heat pump to suit you

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